\thispagestyle{empty}
\subsection*{\centering Abstract}
%IEEE allows italicized abstract
{\em
Parallel computing is playing a critical role in state of the art of 
computation power. The rapid growth of core number is making programs 
running at the most fast speed ever. However, limited by programming 
language and operating system infrastructures, parallel programs might 
not be able to benefit from hardware cores exhaustively. In this report, 
we studied the influence of VMs/emulators on program's parallelism. 
SPLASH-2, REDIS and carefully designed microbenchmarks are carefully selected
and evaluated on QEMU scaled from 1-processor to 32-processor.

Based on the performance results, we concluded that QEMU incurs
certain parallelism bottleneck for particular programs, including FFT in 
SPLASH2-2, but scales well for any basic synchronization operations.
In addition, I/O bound programs scale poors in both native OS and guest OS.

%end italics mode
}

